• Category: web
  • Points: 60
  • Description:

Regular expressions are pretty useful. Especially when you need to search and replace complex terms.


The given website is used to “Search & Replace” with regular expressions. From other challenges we know, that we can execute php code using:


(Check out this Stackoverflow answer for details.)

The problem was, that the website filtered some inputs like:

  • file
  • open

It worked with:


A simple, but nice challenge.